WASHINGTON (AP) — Facing critics on all sides, Homeland Security Secretary Janet Napolitano on Wednesday defended the Obama administration's new policy of deciding which illegal immigrants to send home first.

The government is deporting record numbers of illegal immigrants, she said, but putting at the top of the line those who pose a public safety or national security threat. That's a shift from the Bush administration's enforcement strategy, Napolitano said in a speech at American University, the latest public push to promote the new approach.

Republicans say making it a priority to deport those immigrants amounts to a back-door way of granting amnesty to other people who are living in the U.S. illegally but haven't committed crimes. Yet to immigration advocates, the administration is still deporting such illegal immigrants.

She said policies inherited from the Bush administration "allowed as many resources, if not more, to be spent tracking down and deporting the college student as were spent on apprehending criminal aliens and gang members."

Authorities would conduct large raids at companies without consistently punishing the employer or targeting individuals who posed a threat.

"Public safety wasn't enhanced by these raids, and they sometimes required hundreds of agents and thousands of hours to complete," Napolitano said.

Now, she said, the Department of Homeland Security is using fingerprints collected from those held in local jails to identify and deport criminals and repeat immigration violators

Advocates for an immigration overhaul say this program, known as Secure Communities, has resulted in the deportation of people accused of traffic violations or other misdemeanors. Several states have said they don't want to participate, arguing that immigration is a federal, not state, responsibility.

Napolitano denied that the program had led to more annual deportations and didn't give police immigration authority. She did acknowledge missteps. For example, participation at first was thought to be voluntary, but department officials later made it mandatory.

"But as flawed as the beginnings of this program were, it has already helped accomplish a great deal toward ensuring that we use our enforcement resources where they do the most good," Napolitano said.

She also said the administration was committed to comprehensive immigration changes.

Congressional Republicans have said the government must first secure the border before discussions can turn to an overhaul and have criticized the Obama administration's overall approach to enforcement.

Neither side was satisfied with Wednesday's speech.

GOP Rep. Lamar Smith of Texas, chairman of the House Judiciary Committee, said the administration's immigration policies don't make sense.

"There is nothing smart about it — 7 million illegal immigrants work in the U.S. while 14 million Americans are unemployed," Smith said in a statement. "Worksite enforcement activities are down 70 percent. The Obama administration has abandoned worksite enforcement, allowing illegal workers to take jobs that should go to American workers."

Ali Noorani, executive director of the pro-immigrant National Immigration Forum, said the government needs to move faster in fulfilling promises to target criminals and others who pose a safety threat.

"Fast, sound implementation of the department's deportation prioritization is needed now," Noorani said in a statement. "In this time of scarce dollars and budget crisis, our government should not waste billions on haphazard and unfocused enforcement."

Homeland Security officials have been promoting the criminal targeting effort since Immigration and Customs Enforcement officials announced the arrests of nearly 3,000 criminal illegal immigrants in weeklong, nationwide sweep last week. Those people will now face deportation proceedings.

"We are effectively managing our resources by carrying out our responsibilities in a smart, fair and efficient way," the agency's deputy director, Kumar Kibble, told a House subcommittee Tuesday.

Kibble said that despite the focus on criminals, immigration enforcement for other illegal immigrants hasn't stopped.

In June, the agency's director, John Morton, issued a memo outlining when and how officials could use discretion when deciding which individuals to try to deport.

Among the examples of such cases: young people who were illegally brought to the U.S. by their parents or people without a criminal history who were arrested.

Napolitano, in a letter this summer to senators who have supported comprehensive immigration changes, promised a review of about 300,000 cases pending in federal immigration courts. She wrote that many people who had no criminal history may have their cases delayed indefinitely.

Those people would then be eligible to apply for permission to work in the United States, though such approval is not guaranteed.

Republicans have accused her department of circumventing Congress and creating a policy of administrative amnesty. Napolitano has denied that.